The Effect of Different Sealer Removal Protocols on Micro-Tensile Bond Strength of Single Bond Plus to Dentin Exposed with Different Chemical Root Canal Irrigants: An Ex Vivo Study

Chemical substances used to prepare root canals and their residuals can alter dentin surface composition, affecting restorative systems bonding to dentin.

This ex vivo study evaluated the effects of different sealer removal methodsonthe micro-tensilebondstrength of dentin surfaces exposed using endodontic irrigants.

A total of 45 extracted healthy mandibular molars were sliced from the occlusal surface to expose their dentin surface and were randomly divided into three main groups (n = 15) based on the irrigants as G1: Distilled water (control), G2: Sodium hypochlorite (NaOCL) 5.25%, and G3: Chlorhexidine (CHX) 2%. AH Plus endodontic sealer, was applied to all exposed dentin surfaces. Each group was divided into four subgroups (SG) according to the sealer removal methods SG1: No root canal sealer (control), SG2: Moist cotton pellet, SG3: Ethanol 95% saturated cotton pellet, SG4: Round diamond bur. The teeth were restored using single bond plus and Z250 composite and sectioned to prepare sticks for micro-tensile bond testing. Additionally, failure patterns were investigated. Comparison between experimental groups was performed using Kruskal-Wallis H and Dunn’s post-hoc tests. The accepted significance level for all tests was P < 0.05.

A significant decrease was observed in the micro-tensile bond strength of the control group cleaned with 95% Ethanol saturated cotton pellets. In addition, the highest micro-tensile bond strength was observed in dentin cleaned through a diamond round bur and in the group irrigated with CHX. The failure modes were mainly adhesive.

Within this study’s limitations, the dentin bond strength is affected by the irrigation protocol and sealer removal method.